如何将 Pattern 和 Matcher 与 StringBuffer 或 char[] 类型而不是 String 一起使用？

Question

How can I use a method like this

private boolean respectPattern(String password) {
  Pattern passwordPattern = Pattern.compile(
    "^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)(?=.*[.@$!%*?&])[A-Za-z\\d@$!%*?&.]{8,}$",
    Pattern.CASE_INSENSITIVE);
  Matcher matcher = passwordPattern.matcher(password);
  return matcher.find();
}

If I replace password type with StringBuffer or char[] ?

Answer 1

Method matcher() in class java util.regex.Pattern takes a single parameter whose type is CharSequence which is an interface. According to the javadoc , there are several implementing classes, including StringBuffer . If none of the existing implementations are suitable for your needs, you can always write your own implementation.

For example, using a CharBuffer

CharBuffer cb = CharBuffer.allocate(11);
cb.put(new char[]{'S','e','c', 'r', 'e', 't', ' ', 'P', 'a', 's', 's'});
Pattern passwordPattern = Pattern.compile(
                "^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)(?=.*[.@$!%*?&])[A-Za-z\\d@$!%*?&.]{8,}$",
                Pattern.CASE_INSENSITIVE);
Matcher matcher = passwordPattern.matcher(cb);

Answer 2

if I replace password type with StringBuffer or char[]?

If you replace password type with StringBuffer :

Use as it is ie the following will compile successfully and work as intended:

private boolean respectPattern(StringBuffer password) {
    Pattern passwordPattern = Pattern.compile(
            "^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)(?=.*[.@$!%*?&])[A-Za-z\\d@$!%*?&.]{8,}$",
            Pattern.CASE_INSENSITIVE);
    Matcher matcher = passwordPattern.matcher(password);
    return matcher.find();
}

If you replace password type with char[] :

Use passwordPattern.matcher(String.valueOf(password));